Found out where the main vibration in the rear is coming from

I found out today that the loud vibration at 3000 rpm is coming from the rear "wing" thing at the top of the hatch window that has the red brakelight in the middle of it. I don't know what the hell that thing is called. So anyway, i hit it with my fist, and it made the same vibration noise that the back of the car makes at around 3k rpm. So I'm pretty certain now that that's what I need to address. Incidentally there was no vibration really before I bolted on the Magnaflow exhaust. I think the weird angle that the exhaust hangs at is what's causing the vibration. But anyway.

I need some ideas as to how to pad this wing thing so that it will stop vibrating so goddamn much. Any advice you guys can offer will be appreciated. Thanks.

good thinkin, but one of the four mounting bolts for the hatch window assembly is sheared off. I wonder if that has something to do wiht it. And I don't know that I'm ready to take on boring the thing out and figuring how to get a new threaded bolt piece in there to nut down. But yeah dude, rubber padding was what I was thinking, I just have to head down to pep boys and see if they have something that would fit. Recently I got some 3/4" weather stripping and put it up the sides of the window. That worked pretty good, but I think it transferred the vibration from the window to the next loosest piece, that brake light trim piece. It ended up amplifying it in the end, but at least now it looks like the sides of the window will no longer leak in the rain.

So yeah, I'm gonna have to look for some rubber pad pieces this weekend and see what I can find.
I'm still planning to get the bquiet ultimate and do the great stuff thing in the side panels as soon as I get the dough.

I think I'm gonna try and bore out the sheared bolt shaft and either replace it with the same thing but a higher grade bolt, or just put a nice fat sheet metal screw in there with a washer. If that doesnt work I'm gonna shoot myself, because the loud clunks and vibrations are driving me insane. Sounds like my window is gonna fall off sometimes. I think foam filling the interior panels and putting deadening material throughout will also help with this, but i cant afford the latter right now. I might do the foam this weekend. I just gotta make sure not to bury any wire harnesses that may be inside the panels. Gotta check that out before I start foaming. Other than that my H&R springs and KYB AGXs go on tomorrow afternoon, so hopefully that helps with this too, who knows.

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the springs and shocks will only make it worse. Less vibration/movement will be absorbed by the suspension.

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Great, because my H&Rs and KYBs are going on this weekend. :cry2: BTW, it wasn't that missing nut, because I put two fat sheet metal screws in its place today, and it still makes exactly the same noise. So I'm gonna have to dig even further to find this rattle.

I found today that my magnaflow exhaust is rattling too. I'm wondering if that isn't the core of the problem, since (duh) it wasn't until after I installed it that I had this really bad noise problem. I had to crank the spring bolts on really tight during the exhaust install because of the exhaust and the lack of leeway because of its length, but I'm gonna see if I can't maybe loosen it a little bit. I think that's a lot of what's causing the vibration and clunking. I'm also gonna try and see if there's something in the rear bumper that's loose. Pain in the ass is what this is.

Yep, it's definitely the exhaust thats vibrating and squeaking. When I installed it I thought it was odd that the exhaust hangs at a weird angle due to the orientation of the flange bolt holes. I wonder why that is? So tomorrow I'm gonna see if I can do some kind of modification to it to make it hang straight up and down. Right now the angle it's hanging at is making it rub against the underside of the car in a couple places, so if I can get it to hang right, that should eliminate these noises.

So I spent a couple hours this afternoon working with the magnaflow exhaust to get it to hang properly. My friend, a mechanic, had pointed out to me that the exhaust was rubbing against parts of the heat shields under the car. So, I worked at it for a long time, disconnecting parts of it to get to the heat shield, pounding the heat shield out of the way with a sledgehammer, cutting off the tip of the muffler hanger, and using a air powered cutoff wheel to cut off parts of the heat shield that couldnt be moved, and about an inch off the length of the resonator pipe section to make the exhaust shorter in the middle. In the end, bolted everything back together, and now it hangs a hell of a lot better under there, with no rub.

So I started the car up, and drove it around. The loud ass vibration and rattles are <span style="font-size:18pt;line-height:100%">GONE!</span>

Amazing.

But there's one catch: now that the exhaust is hanging a little lower, now it's bumping down against my 4 point underbrace. :cry2: So now I have to figure out if I can even keep the damn thing on there, or if I can pound the thing a little to move it slighly out of the way of the pipe.